Value of three-dimensional strain parameters for predicting left ventricular remodeling after ST-elevation myocardial infarction

This study was to evaluate the value of multi-directional strain parameters derived from three-dimensional (3D) speckle tracking echocardiography (STE) for predicting left ventricular (LV) remodeling after ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) compared with that of two-dimensional (2D) global longitudinal strain (GLS). A total of 110 patients (mean age, 54?±?9 years) after STEMI treated with primary PCI were enrolled in our study. At baseline (within 24 h after PCI), standard 2D echocardiography, 2D STE and 3D STE were performed to acquire the conventional echocardiographic parameters and strain parameters. At 3-month follow-up, standard 2D echocardiography was repeated to all the patients to determine LV remodeling, which was defined as a 20% increase in LV end-diastolic volume. At 3-month follow-up, LV remodeling occurred in 26 patients (24%). Compared with patients without LV remodeling, patients with remodeling had significantly reduced 2D GLS (?12.5?±?3.2% vs ?15.0?±?3.1%, p?<?0.001), 3D GLS (?9.9?±?2.2% vs ?13.1?±?2.7%, p?<?0.001), 3D global area strain (GAS) (?20.3?±?3.9% vs ?23.3?±?4.8%, p?=?0.005) and 3D global radial strain (GRS) (29.0?±?7.4% vs 34.3?±?8.5%, p?=?0.007) at baseline, but there is no significant difference in 3D global circumferential strain (GCS) (?12.7?±?2.9% vs ?13.0?±?3.2%, p?=?0.822). Separated multivariate analysis shows that 2D GLS, 3D GLS, 3D GAS and 3D GRS all can be independent predictors of LV remodeling. However, receiver-operating characteristic curve analysis showed that the area under the curve of 3D GLS (0.82) for predicting LV remodeling was significantly higher than that of 2D GLS (0.72, p?=?0.034), 3D GAS (0.68, p?<?0.001) and 3D GRS (0.68, p?<?0.001). In patients after STEMI, 2D GLS, 3D GLS, 3D GAS and 3D GRS but not 3D GCS measured after primary PCI are independent predictors of LV remodeling and 3D GLS is the most powerful predictor among them.     

Dobutamine stress echocardiography predicts left ventricular remodeling after acute myocardial infarction.

BACKGROUND AND OBJECTIVES: Left ventricular (LV) remodeling after acute myocardial infarction (MI) is strongly related to infarct size. The contribution of viability in the infarct zone and the presence of multivessel disease remains unknown. Because dobutamine stress echocardiography (DSE) can estimate infarct size and detect myocardial viability and multivessel disease, we postulated that DSE can accurately predict LV remodeling after acute MI. METHODS: To test this hypothesis, 30 patients age 59 +/- 15 years, 21 men, 14 with anterior MI, underwent multistage DSE (low dose, 5 to 10 microg, and peak dose) during the first week after MI occurred. Follow-up echocardiography was performed at >/=1 year. LV remodeling (2 SD increase in LV volume) occurred in 17 of 30 patients. Remodeling occurred in 12 (92%) of 13 patients with large nonviable infarct and in 1 (13%) of 8 patients with large viable infarct (P <.001). Univariate predictors of LV remodeling were baseline ejection infarct (P <.01), infarct size (number of akinetic segments at low dose P <.01), age (P <.05), and multivessel coronary disease (P <. 01). The only multivariate predictor of remodeling was infarct size. Viability of infarct zone was a negative predictor of LV remodeling. CONCLUSION: DSE performed during the first week after acute MI predicts subsequent LV remodeling. Infarct size, nonviability of the infarct zone, and age are independent predictors of LV remodeling. Myocardial viability is a strong negative predictor of LV remodeling.     

Reverse left ventricular remodeling after acute myocardial infarction: the prognostic impact of left ventricular global torsion

Reverse left ventricular (LV) remodeling (>10 % reduction in LV end-systolic volume) may occur in patients recovering for acute ST-elevation myocardial infarction (STEMI), undergoing percutaneous revascularization of infarct-related coronary artery (PCI). To detect whether LV global torsion obtained by two-dimensional speckle-tracking echocardiography was predictive of reverse LV remodeling, 75 patients with first anterior wall STEMI were studied before (T1) and after PCI (T2) and at 6-month follow-up. Two-year clinical follow-up was also accomplished. LV volumes and both LV sphericity index and conic index were obtained by three-dimensional echocardiography. Reverse remodeling was observed in 25 patients (33 %). By multivariate analysis, independent predictors of reverse LV remodeling were: LV conic index, T2 LV torsion and Δ torsion (difference between T2 and T1 LV torsion expressed as percentage of this latter). According to receiver operating characteristic analysis, 1.34°/cm for T2 LV torsion (sensitivity 88 % and specificity 80 %) and 54 % for Δ torsion (sensitivity 92 % and specificity 82 %) were the optimal cutoff values in predicting reverse LV remodeling. In up to 24 month follow-up, 4 non-fatal re-infarction, 7 hospitalization for heart failure and 4 cardiac deaths occurred. By multivariate Cox analysis, the best variable significantly associated with event-free survival rate was reverse LV remodeling with a hazard ratio = 9.9 (95 % confidence interval, 7.9–31.4, p < 0.01). In conclusion, reverse LV remodeling occurring after anterior wall STEMI is associated with favorable long-term outcome. The improvement of global LV torsion following coronary artery revascularization is the major predictor of reverse LV remodeling.     

超声新技术评价急性心肌梗死后左心室重构的研究进展

急性心肌梗死(AMI)后,左心室重构影响患者预后及心血管事件的发生率。超声可早期检测和评价AMI患者左心室重构情况,对临床制定治疗方案、改善预后有重要意义。本文就超声新技术评价AMI后左心室重构的研究进展进行综述。     

黄芪对急性心肌梗死后左室重构的实验研究

目的 观察急性心肌梗死后心室结构的主要变化及心肌局部血管紧张素Ⅱ和羟脯氨酸含量的变化,并观察黄芪的治疗作用。方法 采用兔制备心肌梗死模型,黄芪组自术后第二日腹腔注射黄芪２－３ｍｌ,每日二次,共三周。于术后第六周处死动物,用精确天平及精密卡尺直接测量左室重量、全心重量及梗死区,游离壁和空间隔厚度。采集标本,检测梗死区,游离壁和正常兔心肌血管紧张素Ⅱ和羧脯氨酸含量。结果 梗死后全心重量及左室重量均增加     

黄芪对大鼠心肌梗死后左室重构的影响

目的 :对黄芪对大鼠急性心肌梗死后左室重构的影响及机制作一初步的实验研究。方法 :结扎大鼠冠状动脉制成急性心肌梗死模型 ,随机分组 ,分别予黄芪 ,开搏通、黄芪加开搏通 ,空白治疗 ,每组又按观察时间分为 2周组和 6周组 ,并于观察时间末测收缩压 ,舒张压 ,左室收缩压 ,左室舒张压 ,左室内压最大升降速率。结果 :黄芪、开搏通、黄芪加开搏通均可改善血流动力学 ,而黄芪加开搏通效果最佳。于观察时间末测血浆血管紧张素Ⅱ和醛固酮及心脏局部血管紧张素Ⅱ的浓度 ,发现黄芪可以降低大鼠心梗 6周后血浆和心脏血管紧张素Ⅱ及血浆醛固酮的浓度。于观察时间末对左室作几何测量 ,发现黄芪可减少梗死膨展和左室扩张。结论 :黄芪对大鼠急性心肌梗死后左室重构可产生有益的影响。     

卡托普利防治急性心肌梗死后左室重塑的作用

目的评价血管紧张素转换酶抑制剂(ACEI)卡托普利防治急性心肌梗死(AMI)后左室重塑(LVR)作用。方法对使用ACEI治疗的26例AMI患者(治疗组)与除常规治疗未用ACEI治疗的26例AMI患者(对照组)6个月后NYHA分级Ⅲ级的心衰症状发生率进行比较。结果治疗组1例发生心力衰竭再住院,对照组6例发生心力衰竭再住院,两组存在显著差异(P<0.05)。结论ACEI防治心肌梗死后左室重塑疗效确切。     

心肌梗死后左心室重构与脑钠素的关系

目的:探讨血浆脑钠素水平与急性心肌梗死acutemyocardialinfarction,(AMI)后左室重构的关系,以探讨脑钠素预测心肌梗死预后的可能机制。方法:2003-01/07哈尔滨医科大学第一临床医学院心脏监护病房住院的首次AMI患者185例。选取符合纳入标准的110例为AMI组,男78例,女32例。选择同期本院体检的健康志愿者25例作为对照组,男18例,女7例。所有患者于AMI急性期测定血浆脑钠素浓度,并于取血后24h内以及3个月后行超声心动图检查。根据3个月内左心室容积指标变化将AMI患者分为左心室重构组和非重构组。对比各自的心动超声指标,观察心室重构组与非重构组患者的血浆脑钠素浓度差异。结果:AMI组患者血浆脑钠素浓度犤(416.7±208.0)ng/L犦明显高于对照组对犤(61.8±34.1)ng/L犦(t=2.9,P<0.01)。重构组血浆脑钠素浓度犤(466.3±211.2)ng/L犦明显高于非重构组对犤(301.5±198.7)ng/L犦(t=2.91,P<0.05);而且重构组急性期左室舒张末容积指数明显高于非重构组(t=3.32,P<0.01);左室射血分数明显低于非重构组(t=3.01,P<0.05)。血浆脑钠素浓度与恢复期左室容积指数呈正相关r=0.35,P<0.01)。(结论:AMI急性期血浆脑钠素浓度显著升高,且与AMI后心室重构有关。     

磁共振成像对急性心肌梗死后再灌注损伤和左室重构的评估

背景：磁共振成像对急性心肌梗死的研究多注重心肌灌注改变。目的：分析比较MRI征象中梗死和再灌注心肌的特征，并与病理切片染色结果进行对比。设计：完全随机分组设计，随机对照实验。单位：解放军空军总医院磁共振科，解放军总医院放射科。材料：实验于2003—10／12在解放军总医院动物实验中心完成。选用14只中国小型猪，随机分2组，每组7只，分别为梗死组和再灌注组。分别制成单纯心肌梗死和心肌梗死再灌注动物模型。术前和手术后1个月内多次进行MRI平扫、增强扫描检查。术后1个月取与MRI对应层面及厚度的心脏标本做病理大切片，进行氯化三苯基四氮唑蓝染色检查，对应氯化三苯基四氮唑蓝染色结果分别取梗死心肌（相当于左室前壁）和正常心肌（相当于左室后壁）及其相邻部标本进行苏木精一伊红染色检查观察梗死心肌范围。主要观察指标：两组猪心肌T1和T2弛豫时间改变；梗死和正常心肌的形态改变。结果：纳人中国小型猪14只，梗死组和再灌注组各7只，在造模过程中梗死组死亡1只，进入结果分析猪13只，梗死组6只，再灌注组7只。①T1，T2弛豫时间数值：梗死组梗死区心肌明显大于正常心肌[（1159．54&;#177;78．67），（60．15&;#177;6．31）ma，（1056．15&;#177;70.95），（47．46&;#177;7．94）ma，t=2．63，5．38，P〈0．05，0．01]；再灌注组梗死区心肌也明显大于正常心肌[（1171．14&;#177;139．98），（56．64&;#177;6．16）ms,（1074．64&;#177;97．61），（44．57&;#177;4．25）ma，t=2．64,6．24，P〈0．05，0．01]。②单纯梗死心肌与再灌注梗死心肌在MRI上均有明显强化，但两者弛豫时间和增强特征无明显差别，单纯梗死比再灌注梗死组左室扩大明显。③MRI所见与病理检查结果相对照表明病理切片氯化三苯基四氮唑蓝染色所示梗死区与MRI所见一致。结论：①MRI对心肌梗死以及左室重构评价有价值，MRI和增强扫描不能鉴别梗死和不可逆性再灌注心肌缺血区心肌组织。②再灌注对急性心肌梗死后左室重构改变有治疗作用。③MRI与病理检查具有良好的相关性。     

磁共振成像对急性心肌梗死后再灌注损伤和左室重构的评估

背景磁共振成像对急性心肌梗死的研究多注重心肌灌注改变. 目的分析比较MRI征象中梗死和再灌注心肌的特征,并与病理切片染色结果进行对比. 设计完全随机分组设计,随机对照实验. 单位解放军空军总医院磁共振科,解放军总医院放射科. 材料实验于2003-10/12在解放军总医院动物实验中心完成.选用14只中国小型猪,随机分2组,每组7只,分别为梗死组和再灌注组.分别制成单纯心肌梗死和心肌梗死再灌注动物模型.术前和手术后1个月内多次进行MRI平扫、增强扫描检查.术后1个月取与MRI对应层面及厚度的心脏标本做病理大切片,进行氯化三苯基四氮唑蓝染色检查,对应氯化三苯基四氮唑蓝染色结果分别取梗死心肌(相当于左室前壁)和正常心肌(相当于左室后壁)及其相邻部标本进行苏木精-伊红染色检查观察梗死心肌范围. 主要观察指标两组猪心肌T1和T2弛豫时间改变;梗死和正常心肌的形态改变. 结果纳入中国小型猪14只,梗死组和再灌注组各7只,在造模过程中梗死组死亡1只,进入结果分析猪13只,梗死组6只,再灌注组7只.①T1,T2弛豫时间数值梗死组梗死区心肌明显大于正常心肌[(1159.54±78.67),(60.15±6.31)ms,(1056.15±70.95),(47.46±7.94)ms,t=2.63,5.38,P＜0.05,0.01];再灌注组梗死区心肌也明显大于正常心肌[(1171.14±139.98),(56.64±6.16)ms,(1074.64±97.61),(44.57±4.25)ms,t=2.64,6.24,P＜0.05,0.01].②单纯梗死心肌与再灌注梗死心肌在MRI上均有明显强化,但两者弛豫时间和增强特征无明显差别,单纯梗死比再灌注梗死组左室扩大明显.③MRI所见与病理检查结果相对照表明病理切片氯化三苯基四氮唑蓝染色所示梗死区与MRI所见一致. 结论①MRI对心肌梗死以及左室重构评价有价值,MRI和增强扫描不能鉴别梗死和不可逆性再灌注心肌缺血区心肌组织.②再灌注对急性心肌梗死后左室重构改变有治疗作用.③MRI与病理检查具有良好的相关性.     

超声心动图评价犬急性心肌梗死早期左心室重构的实验研究

目的 采用超声心动图检测犬急性心肌梗死(AMI)后左心室重构发生时间及6 h内左心室重构变化.方法 对14只健康成年犬麻醉后开胸结扎左冠状动脉左前降支制备AMI模型,成功制备8只AMI模型,超声心动图分别于术前,术后1、2、3、4、5及6 h观察梗死心肌室壁厚度(WIT)、室壁运动积分指数(WMSI)、左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)、左心室射血分数(LVEF).检查结束后处死实验犬,取梗死区心肌组织行病理学检查.结果 与术前比较,术后1 h实验犬WMSI、LVESV(P<0.01)和LVEDV(P<0.05)增大,LVEF和WIT减小(P<0.01);WMSI术后3、4、5、6 h高于术后1 h(P<0.05);术后4、5、6 h和术后2 h比较,LVEDV和LVESV增高,LVEF降低.病理检查显示:梗死区心肌细胞发生肿胀,肌浆呈颗粒状凝集而分布不均,出现核固缩.结论 犬AMI后1 h即可出现左心室重构,超声心动图可评估AMI后早期左心室重构.     

择期经皮冠状动脉介入治疗对心肌梗死患者左室重构的影响

目的 :应用二维超声心动图对接受经皮冠状动脉介入治疗的心肌梗死患者术前、术后 6个月各指标进行观测 ,并与未行冠状动脉介入治疗的心肌梗死组比较 ,以探讨经皮冠状动脉介入治疗对心肌梗死患者左室重构的影响。方法 :将 2 7例接受经皮冠状动脉介入治疗的心肌梗死患者作为研究组 ,另取 2 9例未行经皮冠状动脉介入治疗的心肌梗死患者作为对照组 ;经皮冠状动脉介入治疗组分别于术前、术后 6个月完成各指标的测量 ,与对照组的二维超声各指标进行分析 ,以评估经皮冠状动脉介入治疗对左室重构的影响。结果 :两组心肌梗死患者术前二维超声心动图各指标无显著差异 ,经皮冠状动脉介入治疗组术后 6个月与对照组比较左室射血分数 ,短轴缩短率有不同程度改善 ,但尚无统计学意义 ,缩末容量、舒末容量较对照组显著降低 (P<0 .0 5 )。结论 :经皮冠状动脉介入治疗术可改善缺血 ,延缓心肌梗死后的心室重构 ,促进顿抑及冬眠心肌的恢复     

缬沙坦对急性心肌梗死后左室重塑的影响

目的　观察缬沙坦对急性心肌梗死 (AMI)后左室重塑的阻抑作用。方法　将 72例AMI患者随机分为常规治疗组 36例、缬沙坦治疗组 36例 ,并于AMI后 2周、2 4周分别进行超声心动图和平衡法核素心室造影 ,测定左室心肌质量、左室收缩功能和舒张功能 ,了解缬沙坦对AMI后左室重塑的阻抑作用。结果　AMI后 2 4周时 ,缬沙坦与常规治疗组比较 ,室间隔厚度、左室后壁厚度、左室舒张末内径和左室心肌质量指数均明显降低 ,差异有统计学意义(P <0 .0 5或P <0 .0 1)。AMI后 2 4周时 ,缬沙坦治疗组与对照组比较 ,左室射血分数明显增加 (P <0 .0 1) ,左室高峰射血率明显升高 (P <0 .0 1) ,左室高峰射血率时间显著下降 (P <0 .0 5 ) ,同时左室高峰充盈率明显升高 (P <0 .0 5 ) ,左室高峰充盈率时间显著下降 (P <0 .0 1)。结论　缬沙坦能明显减轻心肌梗死后心肌肥厚和左室重塑 ,改善左室功能。     

心肌梗死后心肌细胞凋亡及左室重塑过程中肝细胞生长因子的作用

目的:探讨外源性肝细胞生长因子(hepatocytegrowthfactor,HGF)对心肌梗死后心肌细胞凋亡及左室重塑的影响。方法:将56只新西兰兔随机分为4组:假手术组、假手术+HGF组、对照组和干预组。结扎左冠状动脉前降支复制急性心肌梗死模型。干预组静脉注射给予HGF2mg/(kg·12h),4周后测心功能、左室重塑指标,取出心脏,梗死区/缺血区重量比为梗死范围。TUNEL法染色检测细胞凋亡。Westernblot法测定凋亡蛋白Bcl-2的表达。结果:与假手术组相比,对照组的左室舒张末容积、左室相对重量、左室壁厚度均显著升高(t=3.598,2.348,2.324,P<0.05～0.01),左室缩短分数(leftventricularfractionofshortening,LVFS)、左室射血分数(leftventricularejectionfraction,LVEF)均显著降低(t=4.311,3.330,P<0.01)。HGF干预组LVESV,LVEDV显著低于对照组(t=2.810,2.449,P<0.01);LVFS及LVEF均显著升高。HGF干预组细胞凋亡率、心肌梗死范围均低于对照组(t=2.302,2.344,P<0.01)。左室腔直径与心肌细胞凋亡率呈正相关(r=0.801,P<0.01)。干预组梗死心肌周围bcl-2表达(灰度值1.37)显著高于对照组(灰度值0.17)(t=21.043,P<0.01)。结论:HGF能减少心肌梗死范围、降低心肌细胞凋亡率并能限制心肌梗死后的左室重塑,改善心功能,其作用机制可能与其抗凋     

实时心肌造影超声心动图评价心肌梗死患者血运重建术后左室重构

目的探讨实时心肌造影超声心动图评价心肌梗死患者血运重建术后左室重构的价值。方法20例准备行血运重建术心肌梗死患者,于术前1～5d行常规超声心动图和实时心肌造影超声心动图检查,并于术后3个月再行常规超声心动图检查。室壁运动分析采用18节段分析法,心肌造影灌注分析：按照心肌灌注记分指数（MPSI）分成2组：MPSI≤1．5为心肌灌注良好组;MPSI〉1．5为心肌灌注较差组。分别将：①两组术前左室射血分数（LVEF）、左室收缩末容积（LVESV）、左室舒张末容积（LVEDV）与术后3个月比较;②两组术前的LVEF、LVESV、LVEDV,术后3个月的LVEF、LVESV、LVEDV各自比较;③两组患者手术前后左室射血分数差值（ALVEF）、收缩末容积差值（ALVESV）、舒张末容积差值（△LVEDV）进行比较;④对ALVEF、△LVESV、△LVEDV与MPSI分别做相关性分析。结果MPSI〉1．5组患者手术后3个月的LVEF较MPSI≤1．5组明显减低,LVEDV较MPSI≤1．5组明显增大,MPSI〉1．5组和MPSI≤1．5组患者的ALVEF、ALVEDV存在差别,差异有统计学意义（P〈0．05）;MPSI与ALVEF呈负相关,与△LVESV、△LVEDV呈正相关（P〈0．05）。结论术前MPSI〉1．5组较MPSI≤1．5组发生左室重构的可能性大,实时心肌超影超声心动图能较好的评估心肌梗死患者血运重建术后左室重构情况。